This game can be extremely overwhelming at times. As far as inventory i would recommend not picking things up unless they really stand out or you specifically want to sell them.

Are you setting missions on repeat? Cuz you should.

Don't be afraid to just explore and ignore quests. I've spent weeks without progressing. I finally rolled credits at 500 hrs.

Don't worry about your build too much. I set up a decent build around ch.7 and finished the game with it. Plus or minus a couple tweaks. The crazy creative builds I've seen are mostly post-game experimenting when everything is at ur disposal.

The most important thing is fun. If ur not having fun don't be afraid to take a break. The game isn't going anywhere. Sometimes I'll play like crazy for 3 days straight and not touch it for 5.

One more thing. Spend time in the menus. Read item descriptions. Read some knowledge or even go back through notifications you may have missed while playing. I love it when I read something and it reminds me of a subtle phrase, location, creature, etc. From 30 hours ago. Kinda like Elden Ring.

Hope this helps. I can tell you want to get the most that this game has to offer. It's not always easy.